This invention relates to a rotating drum type heat exchanger. The object of the invention is to provide a heat exchanger able to recover the residual heat in waste fluids of any nature and origin, in particular sludge, waste water, etc., containing solids in suspension, such as discharge waters from chemical processors in general, particularly bleaching and dyeing plants, etc.
A further object of the invention is to provide a heat exchanger of this type that permits, under any operating conditions, a continuous and efficient heat exchange between the two fluids as a function of temperature, and also permits easy accessibility to the different parts of the heat exchanger itself (especially to the parts handling sludge and/or waste water) for periodic cleaning, maintenance, etc.
The heat exchanger according to this invention embodies a shell provided with fittings for inlet and discharge of the fluids to be treated. At least one rotor is rotatably housed in said shell and consists of a series of hollow bodies provided with internal diaphragms to regulate the flow of the other liquid under treatment. These hollow bodies are connected hydraulically to each other in succession, and their ends are joined with adequate fittings by means of rotary seals in order to permit circulation in counter-current of the other liquids under treatment in the rotor.
In one preferred embodiment of the heat exchangers of the of the invention, the shell (which rotatably houses at least one rotor) is provided with perforated supporting gudgeons at its opposite ends. The gudgeons connect the chambers of the hollow bodies with the exterior, and are held by supports connected movably to the side walls of the shell. The openings in the gudgeons are hydraulically interconnected by means of the sealing devices in the fixed gudgeons, which are in turn fastened to a base structure by means of supports which permit convenient rotation of the rotor and capsizing of the shell for cleaning and maintenance of the different parts of the heat exchanger.
The invention will now be described in detail in conjunction with the drawings, which illustrate by way of example only one preferred embodiment of the heat exchanger according to the invention, used mainly (but not exclusively) for heat recovery from waste waters.